Semiconductor device and a method of manufacturing the same

ABSTRACT

A semiconductor device comprising semiconductor chips each formed with plural pads at the main surface, chip parts each formed with connection terminals at both ends thereof, a module substrate on which the semiconductor chips and the chip parts are mounted, solder connection portions for connecting the chip parts and the substrate terminals of the module substrate by soldering, gold wires for connecting the pads of the semiconductor chips and corresponding substrate terminals of the module substrate, and a sealing portion formed with a low elasticity resin such as an insulative silicone resin or a low elasticity epoxy resin for covering the semiconductor chips, chip parts, solder connection portions and gold wires which prevents flow out of the solder in the solder connection portion by re-melting thereby preventing short-circuit.

This is a divisional application of U.S. Ser. No. 10/021,173, filed Dec.19, 2001 now U.S. Pat. No. 6,831,360.

BACKGROUND OF THE INVENTION

This invention concerns a semiconductor manufacturing technique and,more in particular, it relates to a technique useful when applied to amethod of manufacturing a lithium cell monitoring module.

As an example of module products in which surface mounted chip partssuch as chip capacitors or chip resistors and semiconductor chips forbear chip mounting (semiconductor device), those so-called lithium cellmonitoring module have been developed. The chip parts and semiconductorchips are mounted on a module substrate by soldering connection, andboth of them are protected by being covered with a highly elasticinsulative resin.

The structure in which the chip parts (surface mounted parts) and thesemiconductor chips are mounted and both of them are covered with aresin is described, for example, in Japanese Published Unexamined PatentApplication No. 2000-223623 and No. Hei 11(1999)-238962.

At first, Japanese Published Unexamined Patent Application No.2000-223623 describes a technique of making the modulus of elasticity ofa first resin that covers wire bonded semiconductor chips and wiresthereof greater than the modulus of elasticity of a second resin thatcovers the outside thereof to make the first resin harder than thesecond resin to suppress deformation of the first resin by thermalstresses thereby preventing disconnection of the wires.

Further, Japanese Published Unexamined Patent Application No. Hei11(1999)-238962 describes a technique of connecting a semiconductordevice to a substrate by soldering connection by way of solder bumps andalso solder connecting other surface mounted parts to the substrate andfurther covering the semiconductor device and other surface mountedparts with a silicone gel, without wire connection, thereby reducing theoccupying area and the height of the module and reducing the loss.

SUMMARY OF THE INVENTION

However, the present inventor has found the following problems regardingthe semiconductor device of a structure in which the chip parts (surfacemounted parts) and the semiconductor chips are mounted and both of themare covered with resin.

That is, the semiconductor device (such as module products) are solderedby secondary mounting reflow to a mounting substrate such as a printedwiring substrate in which solder is melted again at the soldered parts(surface mounted parts) in the module to cause disadvantages such asshort-circuit.

In this phenomenon, when the solder is melted again, the melt expandingpressure causes peeling at the boundary between the parts and the resinor at the boundary between the resin and the module substrate to whichsolder intrudes in flash to connect terminals on both ends of thesurface mounted parts, leading to short-circuit.

As the countermeasure for the short-circuit, it may be considered astructure in which the internal solder does not melt in the secondarymounting reflow or a structure to moderate the melting expansionpressure of the solder even when it is melted, not to cause peeling atthe boundary between the part and the resin or at the boundary betweenthe resin and the module substrate.

In view of the above, as the former countermeasure, it may be consideredto use a high melting solder for the internal solder. In this case,however, Sn—Pd solder is previously formed to the terminal of thesurface mounted parts and, further, gold plating is applied to theterminals of the module substrate in a module to be applied with wirebonding. Accordingly, it has been found that since impurities such as Snor gold is mixed with the internal solder and the melting point of thesolder is lowered upon secondary mounting reflow of the module even if ahigh melting solder is used to melt the internal solder and, as aresult, the use of the high melting solder is not effective.

On the other hand, as the latter countermeasure, it may be considered touse a gel resin of a low hardness (modulus of elasticity) to moderatethe melting expansion pressure of the molten internal solder but thisinvolves a problem that the protection function (mechanical strength) tothe inside of the module is small.

In this case, while it is possible to protect by covering with a casingor a cap but this involves a problem of increasing the cost.

Further, it may also be considered to use a low melting solder uponsecondary mounting reflow of the module, since the life of the lowmelting solder is short, it gives a problem of low reliability in atemperature cycle test.

Japanese Published Unexamined Patent Application No. 2000-223623 hasneither the description for technique of covering the wire bondedsurface mounted parts (semiconductor chips) with a resin of low modulusof elasticity nor the description of mentioning short-circuit caused bythe melting expansion pressure of the internal solder upon secondarymounting reflow of the module as a problem.

Further, Japanese Published Unexamined Patent Application No. Hei11(1999)-238962 describes a structure of covering the solder connectedsemiconductor devices or other surface mounted parts with a gel resin oflow modulus of elasticity, but it neither contains description for anactual allowable range for the modulus of elasticity of the gel resinnor contains description that points out the short-circuit problemcaused by the melting expansion pressure of the internal solder uponsecondary mounting reflow of the module. Further, it describes astructure covering the outside of the gel resin with a casing, but theuse of the casing gives a problem of increasing the cost.

This invention intends to provide a semiconductor device capable ofpreventing short circuit caused by flowing out of a solder by re-meltingin the semiconductor device, as well as a manufacturing method thereof.

This invention further intends to provide a semiconductor device forreducing the cost, as well as a manufacturing method thereof.

This invention further intends to provide a semiconductor device capableof coping with Pb free trend and a manufacturing method thereof.

These and other objects and novel features of this invention will becomeapparent by reading the description of the specification and theappended drawings.

Outlines of the typical inventions among those disclosed in the presentapplication are simply explained below.

That is, the semiconductor device according to this invention comprisessurface mounted parts mounted by soldering, a wiring substrate on whichthe surface mounted parts are mounted, solder connection portions forconnecting the surface mounted parts to the wiring substrate, and asealing portion formed with an elastic insulative resin for covering thesurface mounted parts and the solder connection portions, in which theelastic resin is a resin having a modulus of elasticity of 200 MPa orless at a temperature of 150° C. or higher.

According to this invention, even when internal solder connectionportions are melted again upon mounting the semiconductor device insecondary mounting reflow, the pressure caused by the melting expansioncan be moderated with the elastic resin and, as a result, it can preventpeeling at the boundary between the surface mounted parts and the resin,or at the boundary between the resin and the module substrate.

This can prevent flow out of the solder to the boundary to preventoccurrence of short circuit between terminals in the surface mountedparts.

Further, the semiconductor device according to this invention comprisesa surface mounted parts to be solder mounted, a wiring substrate onwhich the surface mounted parts are mounted, solder connection portionsfor connecting the surface mounted parts to the wiring substrate, and asealing portion formed with a silicone resin as an elastic insulativeresin for covering the surface mounted parts and the solder connectionportions.

Further, the semiconductor device according to this invention comprisessemiconductor chips as a surface mounted parts formed at the mainsurface thereof with surface electrodes, chip parts as the surfacemounted parts each formed with connection terminals on both endsthereof, a module substrate as a wiring substrate on which thesemiconductor chips and the chip parts are mounted, solder connectionportions for connecting the chip parts to the wiring substrate, and asealing portion formed of a silicone resin which is an elasticinsulative resin for covering the semiconductor chips, the chip partsand the solder connection portions.

Further, the semiconductor device according to this invention comprisessemiconductor chips as the surface mounted parts each formed at the mainsurface with a surface electrode, chip parts as the surface mountedparts each formed with connection terminals on both ends, a modulesubstrate as a wiring substrate on which the semiconductor chips and thechip parts are mounted, solder connection portions for connecting thechip parts to the wiring substrate, and a sealing portion formed of aninsulative resin having a modulus of elasticity of 1 MPa or more and 200MPa or less at a temperature of 150° C. or higher and having a modulusof elasticity of 200 MPa or more at a temperature of 25° C., forcovering the semiconductor chips, the chip parts and the solderconnection portions.

Further, the method of manufacturing the semiconductor device accordingto this invention includes a step of mounting surface mounted parts bysoldering connection to a wiring substrate and a step of covering andresin encapsulating the solder connection portions formed by thesoldering connection and the surface mounted parts with an elasticinsulative resin having a modulus of elasticity of 200 MPa or less at atemperature of 150° C. or higher.

Further, the method of manufacturing a semiconductor device according tothis invention comprises:

a step of providing a substrate to prepare multiple segments in whichplural device regions are partitioned and formed by partition lines; astep of mounting surface mounted parts to the device regions by solderconnection; a step of collectively covering and resin encapsulating thesolder connection portions of plural device regions formed by solderconnection and the surface mounted parts with an elastic insulativeresin and forming a collective sealing portion on the substrate toprepare multiple segments; a step of forming cut-in portions on thesurface of a collective sealing portion along divisional linescorresponding to and on the opposite side of the partition lines of thesubstrate to prepare plural segments; and a step of dividing thesubstrate to prepare multiple segments along the division lines anddividing the collective sealing portion by cut-in portions intoindividual segments.

A method of manufacturing a semiconductor device according to thisinvention comprises: a step of providing a substrate to prepare multiplesegments in which plural device regions are partitioned and formed bypartition lines; a step of mounting surface mounted parts to the deviceregions by solder connection; a step of collectively covering and resinencapsulating the solder connection portions of plural device regionsformed by solder connection and the surface mounted parts with anelastic insulative resin and forming a collective sealing portion on thesubstrate to prepare multiple segments; a step of applyingidentification marks by laser on every device regions on the surface ofthe collective sealing portion; and a step of dividing the substrate toprepare plural segments into segments along division lines correspondingto and on the opposite side of the partition lines.

A method of manufacturing a semiconductor device according to thisinvention comprises: a step of providing a substrate to prepare multiplesegments in which plural device regions are partitioned and formed bypartition lines; a step of mounting surface mounted parts to the deviceregions by solder connection; a step of applying printing by using asqueezer so as to collectively cover solder connection portions ofplural device regions formed by solder connection and the surfacemounted parts with an elastic insulative resin, thereby forming acollective sealing portion on the substrate to prepare multiplesegments; and a step of dividing the substrate to prepare pluralsegments into individual segments along division lines corresponding toand on the opposite side of the partition lines.

A method of manufacturing a semiconductor device according to thisinvention comprises: a step of providing a substrate to prepare multiplesegments in which plural rectangular device regions are partitioned bypartition lines; a step of mounting chip parts and semiconductor chipsas the surface mounted parts by solder connection to the device region;a step of wire bonding the surface electrodes of the semiconductor chipsand the substrate terminals of the device regions of the substrate toprepare multiple segments by forming wire loops of gold wires in thedirection parallel with the longitudinal direction of the deviceregions; a step of collectively covering and resin encapsulating thesolder connection portions of the plural device regions formed by thesoldering connection and the surface mounted parts with an elasticinsulative resin thereby forming a collective sealing portion on thesubstrate to prepare plural segments; and a step of primarily dividingthe substrate to prepare multiple segments with division lines along thelongitudinal direction of the device region and corresponding to andopposite side on the partition lines and secondarily dividing one rowsegment group formed by the primary division along the division lines inparallel with the lateral direction thereof into individual segments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1( a) and FIG. 1( b) are views each showing a structure of an Liion cell monitoring module which is an example of a semiconductor deviceas a preferred embodiment of this invention in which FIG. 1( a) is aperspective view and FIG. 1( b) is a bottom view;

FIG. 2( a) and FIG. 2( b) are views each showing an arrangement ofsurface mounted parts mounted on the Li ion cell monitoring module shownin FIG. 1, in which FIG. 2( a) is a plane arrangement view and 2(b) is across sectional view along A-A in FIG. 2( a);

FIGS. 3( a) and 3(b) are examples of a solder connection structure of achip capacitor in the surface mounted parts shown in FIG. 2 in whichFIG. 3( a) is a cross sectional view and FIG. 3( b) is an enlargedfragmentary cross sectional view showing a portion B in FIG. 3( a);

FIG. 4 is a circuit diaphragm showing an example of a circuit for the Liion cell monitoring module in FIG. 1;

FIG. 5 is a characteristic graph showing an example of a temperaturecharacteristics of a low elasticity resin used for a sealing portion ofthe Li ion cell monitoring module shown in FIG. 1;

FIG. 6 is a graph for melting point data showing an example of a meltingpoint for each of surface mounted parts in the Li ion cell monitoringmodule shown in FIG. 1;

FIG. 7 is a perspective view showing a structure of a multi-layeredceramic substrate as an example of a substrate for preparing multiplesegments used for assembling the Li ion cell monitoring module shown inFIG. 1;

FIG. 8 is a perspective view showing an example of a resin printingmethod in the assembling of the Li ion cell monitoring module shown inFIG. 1;

FIGS. 9( a), 9(b) and 9(c) are views showing an example for a method ofdividing a substrate in assembling the Li ion cell monitoring moduleshown in FIG. 1 in which FIG. 9( a) is a plan view and a bottom view ofa substrate before division, FIG. 9( b) is a plan view for one rowdivision (primary division) and FIG. 9( c) is a plan view for secondarydivision (individual segmentation);

FIG. 10 is a perspective view showing an example of a mounting state ofthe Li ion cell monitoring module shown in FIG. 1 to a mountingsubstrate;

FIG. 11 is an enlarged fragmentary cross sectional view showing anexample of a silicone resin residue upon division of a substrate inassembling the Li ion cell monitoring module shown in FIG. 1;

FIGS. 12( a), 12(b) and 12(c) are views showing an example of a cut instructure of a silicone resin in assembling the Li ion cell monitoringmodule shown in FIG. 1 in which FIG. 12( a) is a substrate-resinperspective view, FIG. 12( b) is a perspective view for the cut inportion and FIG. 12( c) is a perspective view for the groove formed bylaser;

FIG. 13 is a perspective view showing an example of a marking method inassembling the Li ion cell monitoring module shown in FIG. 1;

FIGS. 14( a), 14(b) and 14(c) are views showing an example of a methodof dividing a substrate in assembling the Li ion cell monitoring moduleshown in FIG. 1 in which FIG. 14( a) is a plan view upon one rowdivision (primary division), FIG. 14( b) is a enlarged fragmentaryplanar view for FIG. 14( a) and FIG. 14( c) is a planar view uponsecondary division;

FIGS. 15( a) and 15(b) are process flow charts showing an example of anassembling method and mounting procedures the secondary mounting step ofthe Li ion cell monitoring module shown in FIG. 1 in which FIG. 15( a)is a flow chart for assuming and FIG. 15( b) is a flow chart formounting;

FIG. 16 is an explanatory view for flowing out showing a principle ofsolder flow in a module of a comparative example relative to the Li ioncell monitoring module shown in FIG. 1; and

FIG. 17 is a perspective view showing an example of a solder flow in amodule of the comparative example shown in FIG. 16.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

In the following preferred embodiments, explanation for identical orsimilar portions are not repeated unless it is particularly required.

Further, in the following preferred embodiments, when number and thelike of elements (including number, numerical value, amount and range)are referred to the invention is not restricted to a specified numberand it may be more or less than the specified number excepting for thecase of specifically described or when it is apparently restricted tothe specified number in view of the principle.

Further, in the following preferred embodiments, the constituentelements (including elemental steps) are not always essential except forthe case where they are particularly specified or where they areapparently essential in principle.

In the same manner, when the shape, positional relationship of theconstituent elements are referred to, those substantially equal orsimilar with the shape and the like are also included excepting for thecase where they are particularly specified and in a case where theyshould apparently be excluded in view of the principle. This isapplicable also to the numeral value and the range described above.

Preferred embodiments of this invention will be explained specificallywith reference to the drawings. Through out the drawings for explainingthe preferred embodiments, those members having the same functions carrythe identical reference numerals, for which duplicate explanations areto be omitted.

FIGS. 1( a) and 1(b) are views each showing a structure of an Li ionmonitoring module as an example of a semiconductor device of a preferredembodiment according to this invention in which FIG. 1( a) is aperspective view and FIG. 1( b) is a bottom view, FIGS. 2( a) and 2(b)are views each showing an arrangement of surface mounted parts mountedon the Li ion monitoring module shown in FIG. 1, in which FIG. 2( a) isa planar arraignment view and FIG. 2( b) is a cross sectional view alongA-A in FIG. 2( a), FIGS. 3( a) and 3(b) are views each showing anexample of a solder connection structure of a chip capacitor in thesurface mounted parts shown in FIG. 2 in which FIG. 3( a) is a crosssectional view and FIG. 3( b) is an enlarged fragmentary cross sectionalview showing a portion B in FIG. 3( a), FIG. 4 is a circuit diaphragmshowing an example of a circuit for the Li ion cell monitoring module inFIG. 1, FIG. 5 is a characteristic graph showing an example of atemperature characteristics of a low elasticity resin used for a sealingportion of the Li ion cell monitoring module shown in FIG. 1, FIG. 6 isa graph for melting point data showing an example of a melting point foreach of surface mounted parts in the Li ion monitoring module shown inFIG. 1, FIG. 7 is a perspective view showing a structure of amulti-layered ceramic substrate as an example of a substrate forpreparing multiple segments used for assembling the Li ion monitoringmodule shown in FIG. 1, FIG. 8 is a perspective view showing an exampleof a resin printing method in the assembling of the Li ion monitoringmodule shown in FIG. 1, FIGS. 9( a) to 9(c) are views each showing anexample for a method of dividing a substrate in assembling the Li ionmonitoring module shown in FIG. 1 in which FIG. 9( a) is a plan view anda bottom view of a substrate before division, FIG. 9( b) is a plan viewfor one row division (primary division) and FIG. 9( c) is a plan viewfor a secondary division (individual segmentation), FIG. 10 is aperspective view showing an example of a mounting state of the Li ionmonitoring module shown in FIG. 1 to a mounting substrate, FIG. 11 is anenlarged fragmentary cross sectional view showing an example of asilicone resin residue upon division of a substrate in assembling the Liion monitoring module shown in FIG. 1, FIGS. 12( a) to 12(c) are viewseach showing an example of a cut-in structure of a silicone resin inassembling the Li ion monitoring module shown in FIG. 1 in which FIG.12( a) is a substrate-resin perspective view, FIG. 12( b) is aperspective view for the cut-in portion and FIG. 12( c) is a perspectiveview for the groove formed by laser, FIG. 13 is a perspective viewshowing an example of a marking method in assembling the Li ionmonitoring module shown in FIG. 1, FIGS. 14( a) to 14(c) are views eachshowing an example of a method of dividing a substrate in assembling theLi ion monitoring module shown in FIG. 1 in which FIG. 14( a) is a planview upon one row division (primary division) and FIG. 14( b) is aenlarged fragmentary plant view for FIG. 14( a) and FIG. 14( c) is aplan view upon secondary division, FIGS. 15( a) and 15(b) show processflow charts each showing an example of mounting procedures in theassembling method and the secondary mounting step of the Li ionmonitoring module shown in FIG. 1 in which FIG. 15( a) is a flow chartfor assuming and FIG. 15( b) is a flow chart for mounting, FIG. 16 is anexplanatory view for flowing out showing the principle of solder flow ina module of comparative example relative to the Li ion monitoring moduleshown in FIG. 1. and FIG. 17 is a perspective view showing an example ofa solder flow in a module of a comparative example shown in FIG. 16.

A semiconductor device of this embodiment shown in FIG. 1 is a moduleproduct referred to as an Li (lithium) ion cell monitoring module 1 inwhich surface mounted parts are mounted by soldering on a modulesubstrate 4 and the surface mounted parts are covered with a sealingresin, which is mainly incorporated into a small sized portableelectronic equipments such as a portable telephone.

The function of the Li ion monitoring module 1 is, for example, to turnoff the circuit just before occurrence of abnormality upon short-circuitor over-charging in a portable telephone thereby preventing electricdamages in battery cells.

The Li ion monitoring module 1 comprises, as shown in FIG. 2, asemiconductor chip 2 as a surface mounting part formed with plural pads(surface electrodes) 2 c on a main surface 2 d, chip parts 3 as surfacemounting pads each formed with connection terminals 3 d on both ends, amodule substrate 4 as a wiring substrate on which the semiconductor chip2 and the chip parts 3 are mounted, solder connection portions 5 forconnecting the chip parts 3 and substrate terminals 4 a of the modulesubstrate 4 by means of soldering, gold wires 8 for connecting the pads2 c of the semiconductor chip 2 and the substrate terminal 4 a of thecorresponding module substrate 4 and a sealing portion 7 shown in FIG. 1formed with a low elasticity resin (elastic resin) 6 shown in FIG. 8such as an insulative silicone resin or a low elasticity epoxy resin forcovering the semiconductor chip 2, the chip parts 3, the solderconnection portions 5 and the gold wires 8.

That is, the chip parts to be solder connected on the module substrate 4are covered with the low elasticity resin 6 and thereby the solderre-melting expansion pressure 9 in the solder connection portions 5formed upon secondary reflow (reflow to the mounting substrate at theshipping destination) (refer to Comparative Example in FIG. 16) can bemoderated to prevent peeling at the boundary between the chip part 3 andthe sealing portion 7 and at the boundary between the sealing portion 7and the module substrate 4 and prevent flow out 10 of the solder to theboundary.

The low elasticity resin 6 is a low elasticity and insulative resinhaving both a protective function capable of protecting the interiorparts (mechanical strength) and a flexibility capable of moderating thesolder re-melting expansion pressure 9 shown in FIG. 16. A siliconeresin (silicone rubber) A or low elastic epoxy resins B, C and D havingthe modulus of elasticity shown in FIG. 5 are preferred but existenthigh elasticity epoxy resin T is not suitable.

Then, the allowable range for the modulus of elasticity of the lowelasticity resin 6 (resins A, B, C, D shown in FIG. 5) of thisembodiment is preferably a modulus of elasticity of 200 MPa or less at atemperature of 150° C. or higher while considering high temperature,that is, temperature for the secondary reflow (generally, about 230° C.)or condition of high temperature applied in a temperature cycle test(for example, −40 to +125° C.).

This is a modulus of elasticity capable of moderating the solderre-melting expansion pressure 9 upon melting of the solder at the innersolder connection portions at a high temperature of 150° C. or higherderived from FIG. 5, in which the resins A, B, C and D are within therange but the resin T is out of the range and not suitable.

Further, the low elasticity resin 6 preferably has a modulus ofelasticity of 1 MPa or more at a temperature of 150° C. or higher andthe resins A, B, C and D are within the range as shown in FIG. 5.

This is determined considering the result of a test for protecting thesurface mounted parts in the inside of the sealing portion 7 that theycan be protected so long as the modulus of elasticity is 1 MPa or more.

Further, it should has a modulus of elasticity of at least 1 MPa like inthe above in the same manner as described above also at a temperature ofactual use (normal temperature: 25° C.) and resins A, B, C and D arewithin the range as shown in FIG. 5.

Further, it is further preferred that the resin has a modulus ofelasticity of 200 MPa or more in order to enhance the protection effectfor the surface mounted parts at a temperature of actual use (normaltemperature: 25° C.) and the resins B, C and D are within the range butthe resin A is out of the range as shown in FIG. 5.

However, also the resin A has a modulus of elasticity of 1 MPa or more,there is no particular problem.

In FIG. 5, the rate of occurrence of solder flow out for each of theresins shows the number of failed parts and percentage thereof whenelectrical short-circuit test is conducted for the chip parts 3 whenconducting reflow at 260° C. in which a generator represents the numberof test while the fraction represents the number of failed parts.

According to the test, while rate of the occurrence of failure isextremely low as 0 to 2% in the resins A, B, C and D, the rate ofoccurrence of failure is as high as 70% in the resin T which is notsuitable.

In the reliability test by the temperature cycle, no particular problemsoccur for the resins A, B, C and D.

When the silicone resin (resin A) is adopted, for example, as the lowelasticity resin, the modulus of elasticity of the resin is mostpreferably within a range from 2 to 4 MPa considering the margin for themodule reflow temperature and the mechanical strength (protectivefunction) collectively.

In other words, when the silicone resin (resin A) is adopted forinstance, the shore hardness from A 70 to 80 is a most preferable rangeas the rubber hardness thereof when the margin for the module reflowtemperature and the mechanical strength (protection function) areconsidered collectively.

In FIG. 5, a region P (hatched area) shows an optimal region in thedividing performance of the low elasticity resin 6 when a multi-layeredceramic substrate 11 as a substrate to prepare multiple segments shownin FIG. 7 is divided into individual segments and a region Q (hatchedarea) shows a safety region for the reflow resistance of the lowelasticity resin 6.

Further, in the low elasticity epoxy resins B, C and D shown in FIG. 5,content, for example, of silica contained in each of them is differentand their characteristics are also different to some extent depending onthe content.

The size of the Li ion monitoring module 1 in this embodiment is, asshown in FIG. 1( a), is small as about length (L)=8 to 12 mm, width(M)=3 to 5 mm, height (H)=1.6 mm (MAX). Further, seven externalterminals 1 a are disposed at the rear face thereof as shown in FIG. 1(b).

The pin functions for the seven external terminals 1 a are, for example,GND for the terminal S, CP(−) for the terminal U, TM for the terminal V,CP(+) for the terminal W, VCC for the terminal X, TES for the terminal Yand COM for the terminal Z.

The module substrate 4 is formed, for example, of alumina ceramics.

Then, main surface mounted parts mounted on the Li ion monitoring module1 of this embodiment are to be explained with reference to FIG. 2.

In the Li ion monitoring module 1 described above, two semiconductorchips 2 and six chip parts 3 are mounted as the surface mounted parts onthe module substrate 4 as shown in FIG. 2( a).

One of the two semiconductor chips 2, one is a 2-channel transistor 2 aand the other is a controller 2 b for the monitoring function to controlthe 2-channel transistor 2 a.

Both of them are fixed by the solder connection portions 5 using solderto the substrate terminal 4 a of the module substrate 4 as shown in FIG.2( b). That is, both of the two semiconductor chips 2 are solderconnected to the substrate terminal 4 a by using solder as a die bondingmaterial.

Further, both of them are connected by way of the gold wires 8 to thesubstrate terminals 4 a of the module substrate 4 in which gold wires 8,for example, of 50 μm diameter are use for the 2 channel transistor 2 awhile gold wires 8, for example, of 27 μm diameter are used for thecontroller 2 b.

Further, among the six chip parts 3, three chips are chip resistors 3 b,two chips are ceramic chip capacitors 3 a and one chip is a chipthermister 3 c each of which has connection terminals 3 d on both endsrespectively and each of the connection terminals 3 d is solderconnected with the substrate terminal 4 a at the solder connectionportion 5.

Since the semiconductor chip 2 is wire bonded by using the metal wires8, a gold plating layer 4 b is formed on the surface of each of thesubstrate 4 a as shown in FIGS. 3( a) and 3(b) and, accordingly, each ofthe chip parts 3 is also solder connected to the substrate terminal 4 aformed at the surface with the gold plating layer 4 b.

As shown in FIG. 3( b), the connection terminal 3 d for the chip part 3comprises, for example, an AG—PD electrode 3 e, and an Ni underlyingplating layer 3 f and a solder plating layer 3 g orderly from the lowersurface and the substrate terminal 4 a comprises a Cu member 4 c, an Niunder plating layer 4 d and a gold plating layer 4 b orderly from thelower layer and, further, the region of the substrate terminal 4 a otherthan the place to form the solder connection portion 5 is covered withan overcoat glass 4 e as an insulative film (solder resist film).

Accordingly, in the module substrate 4, the gold plating layer 4 b isformed on the surface for all the substrate terminals 4 a, and the chippart 3 is solder connected at the connection terminal 3 d with the goldplating layer 4 b, and the semiconductor chip 2 is connected at the pad2 c with the gold wires 8 and the gold wires 8 are in turn connectedwith the gold plating layer 4 b on the surface of the substrate terminal4 a.

In this case, wire loops 8 a of the gold wires 8 shown in FIG. 2( b) arebonded so as to be formed in the direction substantially parallel withthe longitudinal direction of a rectangular module substrate 4 as shownin FIG. 2( a).

That is, in the module substrate 4, the substrate terminals 4 a arearranged such that they are wired in the direction substantiallyparallel with the longitudinal direction of the module substrate 4.

FIG. 6 shows melting points of the solder at each of the solderconnection portions 5 in the eight surface mounted parts mounted on themodule substrate 4 and the melting point of the solder alone. It canbeen seen from the graph that the melting point of the chip parts 3(ceramic chip capacitor 3 a, chip resistor 3 b, chip thermister 3 c) islower.

Then, the operation of the circuit for the Li ion monitoring module 1shown in FIG. 4 is to be explained.

In the Li ion monitoring module 1 shown in FIG. 1, the GND terminal isconnected with a (−)terminal of a battery cell and forms an identicalwiring with the VP-terminal connecting to a (−)terminal of a portabletelephone by way of a 2-channel transistor 2 a.

Accordingly, a wiring is a cathode wiring connecting the battery celland the portable telephone.

Further, the 2 channel transistor 2 a is a device for turning circuit toOFF upon occurrence of abnormality. Further, the controller 2 b is adevice for monitoring the potential at each of the wirings forcontrolling the 2 channel transistor 2 a.

Now referring to the actual operation of the circuit shown in FIG. 4specially, the CHG terminal and the DCH terminal of the controller 2 b(monitoring function IC) are at the potential of turning ON the 2channel transistor 2 a and current is supplied from the battery cell tothe portable telephone (current flows from VP(−) to GND).

Then, when abnormality such as short-circuit or flow of large currentoccurs in the portable telephone, a slight potential difference iscaused between the IDT terminal of the controller 2 b and the GNDterminal due to the voltage drop across the slight resistance of the 2channel transistor 2 a, and the potential at the DCH channel reaches apotential to turn OFF one of the channels of the 2 channel transistor 2a by detecting the potential difference.

This can interrupt the supply of current from the battery cell toprevent accidents.

Also during charging, both of the two channels of the 2 channeltransistor 2 a are in the ON state and current is supplied from theportable telephone to the battery cell (current flows from GND toVP(−)).

In a case of overcharging such as excess charging time, since the VCCterminal of the controller 2 b is connected with the positive terminalof the battery cell, when the potential relative to GND exceeds acertain level, the potential at the CHG terminal reaches a potentialwhich turns OFF one of the channels of the 2 channel transistor 2 a bydetecting the excess of the level.

This can stop the current supply from the charger by way of the potabletelephone to the battery cell to prevent the accident.

Then, the method of manufacturing the semiconductor device (Li ionmonitoring module 1) in this embodiment is to be explained in accordancewith the procedures for assembling the module shown in FIG. 15( a).

At first, as shown in step S1, a multi-layered ceramic substrate 11 as asubstrate to prepare multiple segments formed by parting the moduleregion 11 a comprising plural (for example about 120) device regions bypartition lines 11 b is provided.

As shown in FIG. 7, when the module regions 11 a are formed by thenumber of 120 in the multi-layered ceramic substrate 11, the size of thesubstrate is, for example, about (P)80 mm×(Q)80 mm and thickness ofabout 0.5 mm. However, for the substrate to take multiple segments, aglass epoxy substrate other than the multi-layered ceramic substrate 11can also be used.

A circuit shown in FIG. 4 is patterned in each of the module regions 11a and the gold plating layer 4 b shown in FIG. 3( b) is formed on thesurface of each of the substrate terminals 4 a.

Successively, solder paste printing shown in step S2 is conducted andsubsequently plural surface mounted parts are mounted by solderconnection in each of the module regions 11 a (step S3).

That is, after printing the solder paste to each of the substrateterminals 4 a, surface mounted parts such as ceramic chip capacitors 3a, chip thermisters 3 c, chip resister 3 b and semiconductor chips 2 arearranged on predetermined substrate terminals 4 a and, subsequently,reflow is conducted as shown in step S4 to solder connect each of thesurface mounted parts.

The solder in the solder connection portion has a fillet shape as shownin FIG. 2( b).

Subsequently, cleaning shown in step S5 is conducted and, successively,wire bonding shown in step S6 is conducted.

Then, the pad 2 c of the semiconductor chip 2 and the substrate terminal4 a in the module substrate 4 formed with the gold plating layer 4 b atthe surface thereof are wire bonded by using the gold wires 8.

In this case, the wire loops 8 a of the gold wires 8 (refer to FIG. 2(b)) are formed in the direction substantially parallel with thelongitudinal direction of the rectangular module substrate 4 as shown inFIG. 2( a).

Subsequently, resin print coating shown in step S7 is conducted.

In this case, plural semiconductor connection portions 5 of the modulesubstrate 4 formed by the solder connection, the two semiconductor chips2 (2 channel transistor 2 a and the controller 2 b) and the six chipparts 3 (ceramic chip capacitor 3 a, chip resistor 3 b and a chipthermister 3 c) are collectively covered by using an insulative lowelasticity resin 6 such as a silicone resin or a low elasticity epoxyresin as shown in FIG. 5 and printing is conducted by using a squeezer12 as shown in FIG. 8 to form a collective sealing portion 1 on themulti-layered ceramic substrate 11.

That is, as shown in FIG. 8, for the multi-layered ceramic substrate 11completed with mounting of the parts and wire bonding, low elasticityresin 6 such as a silicone resin or a low elasticity epoxy resin iscoated by a printing method so as to cover the plural module regions 11a collectively by the low elasticity resin 6, by using a metal mask 14and a squeezer 12 to form a collective sealing portion 13.

Further, baking and resin curing shown in step S8 is conducted to form aresin coated substrate 15.

That is, the collective sealing portion 13 formed by the printing methodis baked and cured to form the resin coated substrate 15.

Subsequently, division shown in step S9 is conducted to separate themulti-layered ceramics substrate 11 into individual segments.

In the method of manufacturing the Li ion monitoring module 1 in thisembodiment, partition lines 11 b shown in FIG. 7 are formed on thesurface (part mounting side) of the multi-layered ceramic substrate 11and, correspondingly, snap lines (division lines) 11 c as small groovesfor division are formed as shown in FIG. 9( a) and FIG. 11 on theopposite side (rear face) thereof, and the multi-layered ceramicsubstrate 11 is divided (into individual segments) along the snap lines11 c.

Thus, the multi-layered ceramic substrate 11 can easily be divided by amechanical force.

In the division, a multi-layered ceramic substrate 11 formed with thecollective sealing portion 13 shown in FIG. 9( a) is provided and,successively, 1 row division (primary division) shown in FIG. 9( b) isconducted to form 1 row segment group 11 d and, subsequently, individualdivision (secondary division) shown in FIG. 9( c) is conducted to dividethe same into individual modules.

After the division, an electric characteristic test shown in step S10 isconducted to complete a module shown in step 11.

As a result, the Li ion monitoring module 1 shown in FIG. 1 can beassembled.

Then, the secondary mounting step of the module shown in FIG. 15( b) isto be explained.

As shown n FIG. 1( b), external terminals 1 a for solder connection areformed to the rear face of the module substrate 4 of the Li ionmonitoring module 1 such that this can be mounted to a printed wiringsubstrate 16 as a mounting substrate at the shipping destination shownin FIG. 10.

Then, at the shipping destination of the Li ion monitoring module 1, themounting printed wiring substrate 16 which is a PCB substrate isprovided as shown in step S21 and, subsequently, solder paste is printedto the printed wiring substrate 16 as shown in step 22.

Further, after locating the Li ion monitoring module 1 on the printedwiring substrate 16 (module mounting shown in step S23) as shown in stepS23, reflow is conducted as shown in step S24.

That is, as shown in FIG. 10, solder connection portions 5 are formed bysolder reflow to mount the Li ion monitoring module 1 to the printedwiring substrate 16 by reflowing.

Subsequently, as shown in step S25, an electric characteristic test isconducted to complete the mounting shown in step S26.

Explanation is to be made for the characteristic portion that provides afurther effect in the manufacture of the Li ion monitoring module 1according to this invention.

At first, when a low elasticity epoxy resin of a relatively highhardness is adopted, for example, as a low elasticity resin 6, the lowelasticity epoxy resin can be easily divided mechanically in thedividing step shown in step S9 of FIG. 15( a). When a silicone resin isused as the low elasticity resin 6, silicone resin residue 13 b remainsas a portion that can not be divided completely in the silicone resin asshown in FIG. 11.

This is a phenomenon caused by soft characteristics of the siliconeresin.

Then, as a countermeasure for the silicone resin residue 13 b, a cut-inportion 13 a is formed on the surface of the collective sealing portion13 shown in FIG. 12( a) along the snap line 11 c shown in FIG. 9( a) andFIG. 11 corresponding to the partition line 11 b shown in FIG. 7 formedon the surface (part mounting side) of the multi-layered ceramicsubstrate 11, which can prevent occurrence of burrs and improve thedimensional accuracy upon division.

The cut-in portion 13 a is like a V-groove as shown in FIG. 12( b) andthe cut-in portion 13 a is formed by cutting with a cut-in device havinga sharp blade.

Thus, upon division of the multi-layered substrate 11, the multi-layeredceramic substrate 11 is divided along the snap line 11 c and thecollective sealing portion 13 is divided at the cut-in portion 13 a intoindividual segments.

Accordingly, the divisional operability can be improved in a case ofsoft resin such as silicone resin by forming the cut-in portion 13 a inthe surface of the collective sealing portion 13.

Further, instead of the cut-in portion 13 a shown in FIG. 12( b), agroove 13 c may be formed to the surface of the collective sealingportion 13 as shown in FIG. 12( c) by using a laser such as a YAG layeror carbon dioxide gas laser instead of the cut-in portion 13 a show inFIG. 12( b) and the divisional operability can be improved in the samemanner as described above.

In this case, the depth of the groove 13 c can be adjusted bycontrolling the intensity of the laser beam to further improve thedivisional operability.

Further, when the groove 13 c is formed by laser, by using a mechanismcapable of accurately measuring the position for the snap line 11 c inthe multi-layered ceramic substrate 11 by an optical method, the groove13 c can be formed exactly along the line corresponding to the line tobe divided, that is, the snap line 11 c, to improve the divisionaloperability.

Further, when the cut-in portion 13 a shown in FIG. 12( b) or the groove13 c by the laser shown in FIG. 12( c) is formed, the multi-layeredceramic substrate 11 may not always be divided mechanically in thedirection of opening the rear face thereof but it can be mechanicallydivided also in the direction of opening the surface of the collectivesealing portion 13 on the opposite side depending on the dividingapparatus.

In this case, however, it is necessary to form the snap lines 11 c shownin FIG. 11 not on the rear face but on the surface (part mountingsurface) of the multi-layered ceramic substrate 11.

Further, the multi-layered ceramic substrate 11 can also be divided bydicing using a blade rotating at a high speed (cutting blade of agrinding stone) instead of mechanical division shown in FIG. 9.

In this case, the cut face can be fabricated at good dimensionalaccuracy.

This can decrease the clearance of the distance from the cut end to thewiring pattern in view of the design, which is effective to theminiaturizing design for the Li ion monitoring module 1.

Further, when the groove 13 c is formed by using the laser,identification marks 17 such as product numbers shown in FIG. 13 to beformed on the product (Li ion monitoring module 1) can be drawn by theidentical laser in each of the module regions 11 a together withformation of the groove 13 c (refer to FIG. 7).

That is, formation of the grooves 13 c and formation of theidentification marks 17 can be conducted simultaneously to make theoperation efficient.

In a case where the low elasticity resin 6 is a silicone resin, theidentification mark 17 applied by the laser can be formed clearly toprovide an identification mark 17 favorable in view of reading.

This is because the surface of the silicone resin is a gloss surface,whereas the identification marks 17 formed by the laser is baked,engraved and blackened and, accordingly, the identification mark 17 canbe made distinct by bright and dark contrast.

Further, when the multi-layered ceramic substrate 11 is mechanicallydivided, at first the resin coated substrate 15 is primarily divided bysnap lines 11 c in the longitudinal direction of the module region 11 a(refer to FIG. 7) and, after the primary division, the one row segmentgroup 11 d shown in FIG. 14( b) formed by the primary division issecondarily divided along the snap line 11 c parallel with the lateraldirection thereof to divide the same into individual segments as shownin FIG. 14( c).

The electrodes of the module region 11 a shown in FIG. 7 are arrangedsuch that the gold wires 8 are wire bonded in the directionsubstantially parallel with the longitudinal direction of therectangular module region 11 a as shown in FIG. 14( b) upon wirebonding.

It may be considered that an intense force exerts on individual moduleregions 11 a to distort the substrate itself when the rectangularmulti-layered ceramic substrate 11 is divided along the lateraldirection thereof relative to the longitudinal direction upon primarydivision (1 row division) shown in FIG. 14( a). However, when the wirebonding of the gold wires 8 are conducted in the direction of the wireloops 8 a of the gold wires 8, that is, in the direction substantiallyparallel with the longitudinal direction of the module region 11 a, thegold wires 8 are not influenced even when the distortion is caused tothe substrate itself in primary division.

As a result, preferable Li ion monitoring module 1 can be assembled.

According to the semiconductor device (Li ion monitoring module 1) andthe manufacturing method thereof in this embodiment, since thesemiconductor chips 2, the chip parts 3 as the surface mounted parts andrespective solder connection portions 5 are covered with a lowelasticity resin 6 having a modulus of elasticity of 200 MPa or less ata temperature of 150° C. or higher, even when solder connection portion5 in the inside is melted again upon mounting the Li ion monitoringmodule 1 by the secondary mounting reflow, the pressure by the meltingexpansion (solder re-melting expansion pressure 9 shown in FIG. 16) canbe moderated by the low elasticity resin 6.

As a result, this can prevent peeling at the interface between thesurface mounted parts and the resin (low elasticity resin 6) or at theboundary between the resin and the module substrate 4.

This can prevent flow out 10 of the solder to the boundary (refer toFIG. 16) and can prevent occurrence of short-circuit between theconnection terminals 3 d in the surface mounted parts.

As shown in comparative examples of FIG. 16 and FIG. 17, in the soldermounting of a chip part 18, a connection terminal 18 a shown in FIG. 17is plated with 90% SM 10% Pb solder to improve the solder wettability.

For the solder connection portion, a Pb series high temperature solderhaving a melting point (solidus line) of 245° C. is used, that is, amaterial less re-melting in the secondary mounting reflow is selected.

However, in the reflow for module assembling, plating Sn for theconnection terminal is fused into the solder connection portion 18 b toform a Pb—Sn eutectic phase, which lowers the melting point of the Pbseries high temperature solder.

As a result, the solder connection portion 18 b is in a re-molten stateas shown in FIG. 16 upon secondary mounting reflow and, since a resin 20of high hardness is used, the solder re-melting expansion pressure 9 inthe solder connection portion 18 b is increased to become higher thanthe resin pressure 19 to cause defoliation of the boundary between theresin 20 at high hardness and the chip part 18, and the solder flow out10 is formed in flush in the gap to or result in short-circuit failure.

On the contrary, in the Li ion monitoring module 1 according to thisembodiment, since flow out 10 to the solder boundary can prevented.Accordingly, the monitoring module can cope with the secondary mountingreflow.

Further, when the low elasticity resin 6 has a module of elasticity of 1MPa or more at a temperature of 25° C., mechanical protection force(mechanical strength) can surely be maintained.

Accordingly, while preventing the flow out 10 of the solder byre-melting to the boundary, inside of the sealing portion 7 can beprotected effectively.

As a result, since there is no more necessary to cover with a case or acap, the cost can be reduced.

Further, since mechanical division after resin printing coating ormechanical division after printing can be conducted in a state of themulti-layered ceramic substrate 11 by using a silicone resin as the lowelasticity resin 6, sealing or segmentation can be conducted by a methodat a reduced cost.

Accordingly, the cost can be reduced in the manufacture of the Li ionmonitoring module 1.

Further, since occurrence of the flow out 10 of the solder to theboundary by re-melting can be prevented, there is no more required toconsider the lowering of the melting point of the inner solder caused bythe combination of the electrode specification for the surface mountedparts such as the semiconductor chips 2 or the chip parts 3solder-mounted to the Li ion monitoring module 1 and the solder appliedthereto, so that either the solder plating or SN plating may be adoptedfor the electrode specification of the surface mounted parts.

This enables flexible coping along with the progressing situation forreducing the use of Pb in parts manufactures in view of recent Pb-freetrend and, accordingly, the range corresponding to the commercial needscan be extended greatly.

The solder used for assembling the Li ion monitoring module 1 is notnecessarily be a high temperature solder but 60% Sn/40Pb (eutecticsolder) can be used with no problems and this can cope with a case wherehigh temperature can not be applied to the substrate upon assembling themodule by some reasons, without loosing the feature as the Li ionmonitoring module 1.

Further, when a silicone resin is adopted as the low elasticity resin 6,the heat conductivity of the sealing portion 7 can be improved bycontrolling the filler content of the silicone resin, and the thermalresistance as one of important characteristics of the Li ion monitoringmodule 1 can be reduced.

Further, for the inner solder of the Li ion monitoring module 1, asolder having a low melting point in its nature, for example, Pbfree-corresponding solder such as bismuth incorporated solder may alsobe used, not by the depression of the melting point by the melting ofthe part terminal plating of the solder and those having lower meltingpoint than the temperature for the reflow mounting of the Li ionmonitoring module 1 in the shipping destination can be applied with notroubles.

Further, by using the silicone resin for the low elasticity resin 6,since the silicone resin (silicone rubber) is soft, it can reduce thewarp of the module substrate 4 if it is made of a ceramic substrate or aglass-incorporated epoxy substrate and, accordingly, it can reduce thepotential of the troubles in the manufacturing apparatus caused due tothe warp of the substrate in the module assembling step.

Further, by adopting the silicone resin for the low elasticity resin 6,the warp of the module substrate 4 can be reduced even if it is made ofa ceramic substrate or glass-incorporated epoxy substrate, so thatselectivity for the substrate material can be improved.

This invention has been described specifically based on the preferredembodiments of the invention made by the present inventors but theinvention is not restricted to the embodiment of the invention describedabove but can be modified variously within a scope not departing thegist thereof.

For example, in the embodiment described above, the low elasticity resin6 has been explained with reference to an example of a case where thelow elasticity resin 6 is a silicone resin or a low elasticity epoxyresin but the low elasticity resin 6 may also be a gel-like material solong as it is within an allowable range of the modulus of elasticityexplained in the preferred embodiment described above.

Further, in the preferred embodiment described above, explanation hasbeen made to a case where the semiconductor device is an Li ionmonitoring module 1. However, the semiconductor device may be othersemiconductor device such as a high frequency module (high frequencypower amplifier device) so long as it comprises surface mounted parts tobe solder mounted and the surface mounted parts are sealed by the lowelasticity resin 6.

Further, the surface mounting parts are not restricted only to the chipparts or semiconductor chips but may be other electronic parts so longas they are surface mounted parts to be mounted by soldering.

Further, the semiconductor device described above may also be of such astructure that semiconductor chips and a wiring substrate are opposed,and the surface electrodes of the semiconductor chips and the substrateterminals formed at the surface with a gold plating layer, Sn platinglayer or Pb—Sn series solder plating layer are bump connected by way ofgold bumps or solder bumps.

The effects obtained by typical inventions among those disclosed in thepresent application are simply explained as below.

(1) Since the surface mounted parts to be solder mounted and the solderconnection portions thereof are covered with a low elasticity resinhaving a modulus elasticity of 200 MPa or less at a temperatures of 150°C. or higher when the semiconductor device is mounted by reflow insecondary mounting, even if the internal solder connection portion isre-melted, the pressure caused by the melting expansion can be moderatedby the low elasticity resin. As a result, flow out of the solder to theboundary between the surface mounted parts and the resin to prevent theoccurrence of short-circuit between the terminals in the surface mountedparts.

(2) Since the flow out of the solder to the boundary can be prevented,it can cope with the secondary mounting by reflow and when the lowelasticity resin has a modulus of elasticity of 1 MPa or more at atemperature of 25° C., a sufficient mechanical protection force can beensured. Accordingly, since it is no more necessary to cover with acasing or a cap, the cost can be reduced.

(3) Since the resin printing coating or the mechanical division afterprinting can be conducted in a state of a substrate to prepare multiplesegments by the use of the silicone resin as the low elasticity resin,sealing or segmentation can be conducted by a method at a reduced costand, accordingly, the cost can be reduced in the manufacture of thesemiconductor device.

(4) Since the flow out of the solder by re-melting to the boundary canbe prevented, there is no more necessary to consider the lowering of themelting point of the internal solder caused by the combination of theelectrode specification of the surface mounted parts and the solder tobe applied, either the solder plating or Sn plating may be adopted tothe electrode specification for the surface mounted parts. This enablesflexible coping in accordance with the progressing situation for the Pbfree trend in parts manufacturers.

1. A method of manufacturing a semiconductor device comprising the stepsof: mounting surface mounted parts by soldering connection to a wiringsubstrate; and covering and resin encapsulating solder connectionportions formed by the solder connection and the surface mounted partswith an elastic insulative resin having a modulus of elasticity of 200MPa or less at a temperature of 150° C. or higher.
 2. A method ofmanufacturing a semiconductor device according to claim 1, wherein resincapsulation is conducted with an elastic insulative resin having amodulus of elasticity of 1 MPa or more at a temperature of 150° C. orhigher upon resin encapsulation.
 3. A method of manufacturing asemiconductor device according to claim 1, wherein a resin having amodulus of elasticity of 1 MPa or more at a temperature of 25° C. isused for the elastic resin.
 4. A method of manufacturing a semiconductordevice according to claim 1, wherein a resin having a modulus ofelasticity of 200 MPa or more at a temperature of 25° C. is used for theelastic resin.
 5. A method of manufacturing a semiconductor deviceaccording to claim 1, wherein a silicone resin is used as the elasticresin.
 6. A method of manufacturing a semiconductor device according toclaim 1, wherein chip parts as the surface mounted parts are mounted bysoldering to substrate terminals each formed with a gold plating layer,an Sn plating layer or Pb—Sn series solder plating layer at the surfaceof the wiring substrate.
 7. A method of manufacturing a semiconductordevice according to claim 6, wherein surface electrodes of semiconductorchips as the surface mounted parts and the substrate terminals eachformed with a gold plating layer, an Sn plating layer or a Pb—Sn seriessolder plating layer at the surface are wire bonded by gold wires.
 8. Amethod of manufacturing a semiconductor device according to claim 7,wherein the semiconductor chips and chip parts are mounted on arectangular module substrate as the wiring substrate and, subsequently,wire loops of the gold wires are formed in a direction parallel with thea longitudinal direction of the module substrate when the surfaceelectrodes of the semiconductor chips and the substrate terminals arewire bonded by the gold wires.
 9. A method of manufacturing asemiconductor device comprising the steps of: (a) providing a modulesubstrate having a plurality of substrate terminals over a main surfaceand a plurality of external terminals over a back surface opposite tothe main surface; (b) mounting a semiconductor chip over a firstsubstrate terminal of the plurality of substrate terminals; (c) mountinga chip part having two connection terminals over second substrateterminals of the plurality of substrate terminals by means of solderingso that the two connection terminals and the second substrate terminalsare connected via solder; and (d) forming a silicone resin over the mainsurface of the module substrate to cover the semiconductor chip and thechip part, wherein the semiconductor device is mountable over a mountingsubstrate by means of soldering; and wherein the silicone resin has amodulus of elasticity of 200 Mpa or less at a temperature of 150° C. orhigher and 1 Mpa or more at a temperature of 25° C.
 10. A method ofmanufacturing a semiconductor device according to claim 9, wherein atemperature of about 230° C. is applied when the semiconductor device ismounted over the mounting substrate.
 11. A method of manufacturing asemiconductor device according to claim 9, wherein in the step (d), thesilicone resin is formed by a print coating method.
 12. A method ofmanufacturing a semiconductor device according to claim 9, wherein thesilicone resin has a modulus of elasticity of 200 Mpa or less at atemperature of 200° C. or higher.
 13. A method of manufacturing asemiconductor device according to claim 9, wherein the semiconductordevice is a high frequency power amplifier device.
 14. A method ofmanufacturing a semiconductor device according to claim 9, wherein theexternal terminals of the module substrate are adapted for connecting tothe mounting substrate via solder.
 15. A method of manufacturing asemiconductor device according to claim 9, wherein a gold plating layeris formed on each of the second substrate terminals.